Genome-wide identification of NAC gene family and expression analysis under abiotic stresses in Salvia miltiorrhiza.

NAC (NAM, ATAF, CUC) is a class of transcription factors involved in plant growth regulation, abiotic stress responses, morphogenesis and metabolism. Salvia miltiorrhiza is an important Chinese medicinal herb, but the characterization of NAC genes in this species is limited. In this study, based on the Salvia miltiorrhiza genomic databases, 82 NAC transcription factors were identified, which were divided into 14 groups. Meanwhile, phylogenetic analysis, gene structure, chromosomal localization and potential role of SmNACs in abiotic stress conditions were also studied. The results revealed that some SmNACs had different structures than others, which advised that these genes may have multiple/distinct functions. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis showed that SmNACs exhibited differential expression patterns under salt and drought stress. The NaCl induced salinity treatments modulated the expression of several SmNAC genes more in roots compared with leaves. Conversely, under drought stress conditions, more genes were upregulated in leaves compared with roots. These results will be useful for the further study involved in the functional characteristics of SmNAC genes, especially in response to salt and drought stresses, thereby may facilitate genetic breeding in Salvia miltiorrhiza. [ABSTRACT FROM AUTHOR]